Author Topic: Seat fixing  (Read 274 times)

Offline JHG1958

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Seat fixing
« on: 15.08. 2020 12:38 »
My seat needs a bit of welding to restore the captured nuts.  I will probably get a new cover at the same time.

But all is not as it seems. Although my bike is a 1961 A10 GF it looks like a pre 1959 seat with a dip in the middle and white piping. No problem I think I prefer this type.

The front bracket looks like a custom job. See photo. This was probably to cope with the loss of one of the captured nuts on the seat.  This is fine but should there not be a lump of rubber part number 42-9057 here?  If I use this bracket there will be no room without making the seat too high.  Does anyone put a lump of rubber under the front bracket?

It would great to have the dimensions from a real bracket specifically from the slot to the the top where it bolts onto the seat. Mine is 1” from the top of the slot to the top of the bracket (underside of the seat pan).

The rear bracket is a bit of mess too.  There is a newish one that sits on top of the mudguard as per 1954-59 models but this is a little low.  I could make some new ones that bolt onto the side of the mudguard that has fixing holes anyway or else use some rubber to raise the seat 1/2 inch.  Are both fixing systems equally good?  If I make new brackets am tempted to use the suspension mountings as I need to weld the seat pan anyway.  Does anyone know why they bolt onto the mudguard rather than the suspension?

Finally if I do get it welded, I was going to get studs welded rather than captured nut.  Getting a nut welded square is more difficult than getting a stud plumb.  I cannot see why BSA did not use studs anyway, what am I missing?

Derbyshire, England. 1961 Golden Flash S/Arm

Offline Swarfcut

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Re: Seat fixing
« Reply #1 on: 15.08. 2020 14:15 »
Captive nuts are just that. Assemble everything on the seat pan, then just tack weld the nuts in place. Everything will fit as you have fixed the nuts in their final all tightened up position.

 Car exhaust mountings, the sort with two threaded studs bonded to a rubber block ("cotton reels") make a handy and compliant rear seat mount, and a custom mount from the frame will be a better way to support the seat pan, avoiding extra load on the relatively weak rear mudguard.  The original design, as always, is a compromise between the designer, production engineers and cost accountants......


Offline lawnmowerman

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  • 1959 Super Rocket. Kent, England
Re: Seat fixing
« Reply #2 on: 15.08. 2020 14:39 »
But all is not as it seems. Although my bike is a 1961 A10 GF it looks like a pre 1959 seat with a dip in the middle and white piping. No problem I think I prefer this type.

Although the seats did have a dip in the middle, on some it is really pronounced. This is usually due to the rubber buffers fitted to the frame being wrongly adjusted (or missing). If the rider is of generous proportions (like me) the seat pan then bends in the middle. Sometimes done on purpose for those with short legs.
Occasionally the rubber buffers fall off - I superglued mine to the bolt heads.

I made some posts a while ago with comparisons of the various seats and if your bike is a 61 it should have a wider seat according to Leightons. This is what I have on my 59 and it feels more comfortable than the earlier type which I think you have. I ended up making the rear bracket to get it closer to the mudguard having tried the standard and RGS brackets.

1959 A10 SR
1938 Wolseley 14/60
1955 Ferguson TEF20 tractor
1965 Ferguson 135 tractor
1952 Matchless G80 rigid
1960 BMW R60
1954 Matchless G80S
1955 Ariel 500 VH
1951 Sunbeam S7DL
1960 Matchless G12 with Watsonian Monza
......and loads of lawnmowers

Too old to Rock and Roll but too young to die  (Jethro Tull 1976)

Online RichardL

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Re: Seat fixing
« Reply #3 on: 15.08. 2020 19:41 »
Plan on signing up for the world-wide 2020 DISTINGUISHED GENTLEMAN'S RIDEon September 27, 2020. This year it's a solo or pillion ride in dapper attire. Watch website at for details.

Online Bsareg

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Re: Seat fixing
« Reply #4 on: 16.08. 2020 15:52 »
For an extra £1.80 delivered, they're available from CPC Eng in stainless fit and forget.
C11,B40,B44 Victor,A10,RGS,M21,Rocket3,REBSA